As stated on the opening page of this site, development of the NHSE has been funded by federal High Performance Computing and Communication (HPCC) agencies. Among the goals of the NHSE is to promote sharing and distribution of software and related resources developed by these agencies. Below is a list of links to information about three of the major HPCC programs currently in progress.
Department of Defense's High Performance Computing Modernization Program (HPCMP):
Department of Energy's Accelerated Stragic Computing Initiative (ASCI): National Science Foundation (NSF) funded Supercomputing Metacenters: